Understanding total power load on an Arduino Uno

Projects General Guidance
1

I am working on a hobby project for a laser tripwire system. As of now have successfully made a simple system with a Laser Transmitter, Laser Receiver Sensor Module (Non-modulator), two blinking LEDs and a Buzzer which alerts when the laser is not detected.

Now I want to improve on it by making it 3 lasers and sensors instead of just one, ideally stacking them up. This was I can avoid a lot of false positive alerts which happens because of bugs and have the alert fired ONLY when all the 3 lasers are tripped.

My concern is whether the power requirements for 3 lasers, 3 sensors, 2 LEDs and buzzer etc. would all be available on the board and whether it can run that way for a long time. I am not very good with current ratings but from what I understand each digital pin can supply 40 mA of current and each of these input/output sensors require around the same power.

So considerin 3 laser + 3 sensor + 2 LEDs + 1 buzzer + 1 switch = 10 pins, I will be using all of the digital pins available on the board. Would this work or am I overloading the board?

I am quite new to this, so if there is an additional resource that can help explain this, please point me to the same. Thanks!

2

Welcome to the forum

You have omitted the crucial data as to how much current each device needs

3

That is the ABSOLUTE MAXIMUM for the Uno and you don't want to be anywhere near that value. The recommended output current for an Uno is 20mA

4

You are WAY overloading.

5

That is wrong for a start, 40mA is the point at which damage is done.

So you are missing what Arduino Board you are using, and a schematic so we can see how physically these devices are being wired up.

Consider the ratings for an Arduino Uno R3.

Pin Abs limits
Pin Abs limits1690×546 71.6 KB

Pin Conditions
Pin Conditions1598×536 81.2 KB

6

What Uno board?
What laser, link or specs?
Can't you just power transmitters directly from 5V, not through arduino digital pins.

9

Lasers are rarely used for beambreak/tripwires, except for in movies.
Better to use modulated infrared, which is less sensitive to false triggering from other light sources (sunlight, etc.).
What distance do you need to bridge. indoors or outside.
Leo..